The death toll in the central Mediterranean has fallen in the past year, but the number of those drowning as a proportion of arrivals in Italy has risen sharply. Photograph: Juan Medina/Reuters

The first non-military, Italian-flagged, rescue boat to operate in the Mediterranean since the migration crisis began has left for wate rs off Libya, in a direct challenge to Italyâs far-right interior minister, Matteo Salvini.

UN calls on EU states to offer asylum and end Italyâs migrant standoff Read more

NGO rescue boats have all but disappeared from the main migration routes since Salvini announced soon after taking office this summer that he was closing Italian ports to non-Italian rescue vessels.

The Italian flag on the 38-metre Mare Jonio will make it harder for Salvini to prevent it from docking, though he could still move to prevent people from disembarking. The boat has been bought and equipped by a coalition of leftwing politicians, anti-racist associations, intellectuals and figures in the arts, under the supervision of two NGOs. Its mission has been called Mediterranea.

âWe want to affirm a principle of humanity that rightwing policies seem to have forgotten,â Erasmo Palazzotto from the leftwing LeU (Free and Equal) party said.

Anti-immigration policies by the Maltese and Italian governments, which have closed their ports to rescue vessels, have driven a sharp decrease in rescue missions. People seeking asylum are still attempting the risky crossing. But without the rescue boats, shipwrecks are likely to rise dramatically.

In August, Salvini refused a landing to 177 people saved in the central Mediterranean by an Italian coastguard ship. The vessel was authorised to dock at the port of Catania but the people on board were forced to remain on board for alm ost a week.

ââShould we expect Salvini to close the ports to us too? We are an Italian boat, flying the Italian flag. They will have to answer to this,â Palazzotto said. âIf they then attempt to refuse to let the migrants disembark we will not remain silent and will give voice to them from the ship.â

The ship has received support from the Spanish NGO Pro-Activa and the aid group Seawatch, as well as the writer Elena Stancanelli and the film director Paolo VirzÃ¬.

âThis is a moral disobedience mission but also a civil obedience one,â the Mediterranea mis sionâs press office said in a statement. âWe will disobey nationalism and xenophobia. Instead we will obey our constitution, international law and the law of the sea, which includes saving lives.â

The death toll in the central Mediterranean has fallen in the past year, but the number of those drowning as a proportion of arrivals in Italy has risen sharply in the past few months, with the possibility of dying during the crossing now three times higher. So far in 2018, 21,041 people have made the crossing and 1,260 have died.